package 第四章作业.O407;

import java.util.Scanner;

public class Area4 {
    public static void main(String[] args){
        System.out.println("请输入圆的半径：");
        Scanner reader = new Scanner(System.in);
        double a = reader.nextDouble();
        CircularArea(a);
    }
    public static void CircularArea(double r){
        double pi = 3.14;
        System.out.printf("圆的周长、面积为%.2f、%.2f",pi*2*r,pi*r*r);
    }
}
